1. Technical Field
The present invention relates to a method and an apparatus for adjusting the parameters of a magnetic resonance image, more particularly to a method and apparatus with which the parameters of a magnetic resonance image can be easily altered during a diagnostic procedure using MRI.
2. Description of the Related Art
A magnetic resonance image (MRI) is an image that is obtained by having a person's body enter an apparatus equipped with a large magnet which generates a magnetic field, generating radio waves to resonate the nuclei of hydrogen atoms in a body part, measuring the differences in signals emitted from the respective tissues, and reconstructing the image with a computer.
That is, radio waves are emitted to the body from an apparatus equipped with a magnet, and as echo signals are obtained from the body, the echo signals are collected and converted into digital information for imaging.
Unlike X-ray radiography or CT scanning, which are tests that use X-rays, magnetic resonance imaging is a test method which uses radio waves of nonionizing radiation and thus provides the important advantage that it is essentially harmless to the human body. Using a magnetic field and radio waves of nonionizing radiation, which are harmless to the human body, magnetic resonance imaging provides a higher contrast for soft tissues in the body compared to CT scanning, even without the use of contrast agents, and provides information regarding the biochemical properties of tissues that contain hydrogen nuclei.
While it is similar to CT scanning in that cross-sections of the body can be obtained, magnetic resonance imaging can freely provide images along a desired direction, such as along a transverse direction, a longitudinal direction, a diagonal direction, etc., without requiring the patient to change posture, whereas a CT scan is generally focused on transverse cross-sections that show the body intersected laterally. A magnetic resonance image can be obtained via various techniques, the most well-known examples including T1 weighted imaging, T2 weighted imaging, FLAIR (fluid-attenuated inversion recovery), etc.
A T1 weighted image is an image that is obtained by a spin echo technique using a short TR (repetition time) and a short TE (echo time), where the image is obtained by a technique that reflects differences in T1 relaxation times as signal differences. When a short TR is used, the degrees of recovery of longitudinal magnetization may differ greatly between the tissues, and this may be reflected in the signals to obtain a T1 weighted image.
A T2 weighted image is an image that is obtained by a spin echo technique using long TR and TE, where the image is obtained by a technique that reflects the tissues' differences in T2 relaxation times as signal differences. When a long TR is used, the transverse magnetization decay may differ greatly between the tissues, and this may be reflected in the signals to obtain a T2 weighted image.
A FLAIR image is an image obtained by an inversion recovery technique that uses 180-degree inversion pulses.
A doctor may diagnose a patient's condition by using an image obtained from an imaging device according to any one of the various techniques (sequences) above.
However, the procedure here may entail diagnosing the patient using an image obtained by one MRI technique, and when insufficient, acquiring another image obtained by another technique, so that the patient may have to undergo repeated procedures of image capturing for different sequences for the diagnosis.
Recently, there has been research conducted on obtaining images that may be predicted when certain parameters (e.g. the TE and TR) are adjusted from MR data.
However, the image suited for diagnosing a patient may differ according to the condition of the patient, and it may be difficult for a doctor to predict which parameters need to be inputted in order to obtain a suitable image.